Design and fabrication of inverted tapered micro-pillars for spontaneously transporting liquid upward

Abstract

Directional liquid transport has significant domestic and industrial applications. Theoretically, tapered objects can transport a liquid droplet horizontally or along a small slant angle: Many biomaterials have already demonstrated this ability. However, spontaneously transporting liquid in the vertical direction has been challenging. In this study, a numerical model was developed to simulate the transporting process and design inverted tapered pillars. The range of acceptable parameters for the pillar’s geometry was obtained. When the taper angle, the diameter of the bottom end of the pillar, and the contact angle of the liquid are less than 10°, 80 μm, and 54.5°, respectively, then liquid may be transported upward spontaneously. An experimental setup for fabricating the pillars was also developed and presented. With this setup, the designed pillars were successfully fabricated by the gradient electrochemical corrosion method and enhanced its wettability by the electrochemical modification method. The fabricated pillars were then experimentally validated, showing that they can spontaneously transport a micrometer-scale droplet upward. These results may provide a new and systematic way to design and fabricate a tool for high-efficiency liquid transport.

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References

  1. Basaran OA, Suryo R (2007) Fluid dynamics: the invisible jet. Nat Phys 3(10):679–680

    Article  Google Scholar 

  2. Bico J, Quéré D (2002) Self-propelling slugs. J Fluid Mech 467:101–127

    Article  MATH  Google Scholar 

  3. Chen Y, Guo M, Yang K, Wang C (2013) Enhanced cooling for LED lighting using ionic wind. Int J Heat Mass Transf 57(1):285–291

    Article  Google Scholar 

  4. Cheng J, Sun Y, Zhao A, Huang Z, Xu S (2015) Preparation of gradient wettability surface by anodization depositing copper hydroxide on copper surface. Trans Nonferr Met Soc 25(7):2301–2307

    Article  Google Scholar 

  5. Chu PK, Liu X (2008) Biomaterials fabrication and processing handbook. CRC Press, Boca Raton

    Google Scholar 

  6. Dai Q, Khonsari MM, Shen C, Huang W, Wang X (2016) Thermocapillary migration of liquid droplets induced by a unidirectional thermal gradient. Langmuir 32(30):7485–7492

    Article  Google Scholar 

  7. Eggers J, Villermaux E (2008) Physics of liquid jets. Rep Prog Phys 71(3):36601

    Article  Google Scholar 

  8. Ferraro P, Coppola S, Grilli S, Paturzo M, Vespini V (2010) Dispensing nano-pico droplets and liquid patterning by pyroelectrodynamic shooting. Nat Nanotechnol 5(6):429–435

    Article  Google Scholar 

  9. Guo L, Tang GH (2015) Experimental study on directional motion of a single droplet on cactus spines. Int J Heat Mass Transf 84:198–202

    Article  Google Scholar 

  10. Guo MT, Rotem A, Heyman JA, Weitz DA (2012) Droplet microfluidics for high-throughput biological assays. Lab Chip 12(12):2146–2155

    Article  Google Scholar 

  11. Huang JY, Lo Y, Niu JJ, Kushima A, Qian X, Zhong L, Mao SX, Li J (2013) Nanowire liquid pumps. Nat Nanotechnol 8(4):277–281

    Article  Google Scholar 

  12. Ju J, Bai H, Zheng Y, Zhao T, Fang R, Jiang L (2012) A multi-structural and multi-functional integrated fog collection system in cactus. Nat Commun 3:1247

    Article  Google Scholar 

  13. Ju J, Xiao K, Yao X, Bai H, Jiang L (2013) Bioinspired conical copper wire with gradient wettability for continuous and efficient fog collection. Adv Mater 25(41):5937–5942

    Article  Google Scholar 

  14. Ju J, Zheng Y, Jiang L (2014) Bioinspired one-dimensional materials for directional liquid transport. Acc Chem Res 47(8):2342–2352

    Article  Google Scholar 

  15. Katsikis G, Cybulski JS, Prakash M (2015) Synchronous universal droplet logic and control. Nat Phys 11:588–597

    Article  Google Scholar 

  16. Li EQ, Thoroddsen ST (2013) The fastest drop climbing on a wet conical fibre. Phys Fluids (1994-present) 25(5):52105

    Article  Google Scholar 

  17. Li K, Ju J, Xue Z, Ma J, Feng L, Gao S, Jiang L (2013) Structured cone arrays for continuous and effective collection of micron-sized oil droplets from water. Nat Commun 4:2276

    Google Scholar 

  18. Li J, Wang D, Duan JA, He H, Xia Y, Zhu W (2015) Structural design and control of a small-MRF damper under 50 N soft-landing applications. IEEE Trans Ind Inform 11(3):612–619

    Article  Google Scholar 

  19. Li J, Zhang X, Zhou C, Zheng J, Ge D, Zhu W (2016) New applications of an automated system for high-power LEDs. IEEE-ASME Trans Mech 21(2):1035–1042

    Article  Google Scholar 

  20. Liang Y, Tsao H, Sheng Y (2015) Drops on hydrophilic conical fibers: gravity effect and coexistent states. Langmuir 31(5):1704–1710

    Article  Google Scholar 

  21. Lorenceau É, Quéré D (2004) Drops on a conical wire. J Fluid Mech 510:29–45

    Article  MATH  Google Scholar 

  22. Luo C (2015) Theoretical exploration of barrel-shaped drops on cactus spines. Langmuir 31(43):11809–11813

    Article  Google Scholar 

  23. Lv C, Chen C, Chuang Y, Tseng F, Yin Y, Grey F, Zheng Q (2014) Substrate curvature gradient drives rapid droplet motion. Phys Rev Lett 113(2):26101

    Article  Google Scholar 

  24. Madou MJ (2011) Manufacturing techniques for microfabrication and nanotechnology, vol 2. CRC Press, Boca Raton

    Google Scholar 

  25. Michielsen S, Zhang J, Du J, Lee HJ (2011) Gibbs free energy of liquid drops on conical fibers. Langmuir 27(19):11867–11872

    Article  Google Scholar 

  26. Park K, Kim P, Grinthal A, He N, Fox D, Weaver JC, Aizenberg J (2016) Condensation on slippery asymmetric bumps. Nature 531(7592):78–82

    Article  Google Scholar 

  27. Price AK, Paegel BM (2016) Discovery in droplets. Anal Chem 88(1):339–353

    Article  Google Scholar 

  28. Rowlinson JS, Widom B (2013) Molecular theory of capillarity. Courier Corporation, Chelmsford

    Google Scholar 

  29. Subramanian RS, Moumen N, McLaughlin JB (2005) Motion of a drop on a solid surface due to a wettability gradient. Langmuir 21(25):11844–11849

    Article  Google Scholar 

  30. Tong WL, Tan MK, Chin JK, Ong KS, Hung YM (2015) Coupled effects of hydrophobic layer and vibration on thermal efficiency of two-phase closed thermosyphons. RSC Adv 5(14):10332–10340

    Article  Google Scholar 

  31. Vorobyev AY, Guo C (2009) Metal pumps liquid uphill. Appl Phys Lett 94(22):224102

    Article  Google Scholar 

  32. Wang Q, Meng Q, Chen M, Liu H, Jiang L (2014) Bio-inspired multistructured conical copper wires for highly efficient liquid manipulation. ACS Nano 8(9):8757–8764

    Article  Google Scholar 

  33. Wang Q, Meng Q, Liu H, Jiang L (2015) Chinese brushes: From controllable liquid manipulation to template-free printing microlines. Nano Res 8(1):97–105

    Article  Google Scholar 

  34. Wu S, Yang C, Hsu W, Lin L (2015) 3D-printed microelectronics for integrated circuitry and passive wireless sensors. Microsyst Nanoeng 1:1–9

    Article  Google Scholar 

  35. Yuan Y, Lee TR (2013) Contact angle and wetting properties. Springer, Berlin

    Google Scholar 

  36. Zheng Y, Bai H, Huang Z, Tian X, Nie F, Zhao Y, Zhai J, Jiang L (2010) Directional water collection on wetted spider silk. Nature 463(7281):640–643

    Article  Google Scholar 

  37. Zhu H, Guo Z, Liu W (2016) Biomimetic water-collecting materials inspired by nature. Chem Commun 52(20):3863–3879

    Article  Google Scholar 

Download references

Acknowledgements

The work presented in the paper is partially supported by National Natural Science Foundation of China (51605100, U1601202), Fund of Guangdong R&D Science and Technology (2016A010102016, 2017A030313314, 2016A030308016, 2015B010104008, 2015B010133005), Guangzhou General Programs for Science and Technology Development (201707010446), and Hong Kong Research Grants Council (14243616, CityU:11207714).

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Y.C carried out the experiments and drafted the manuscript. D.S, X.M, and L.L helped the experiments. J.G, X.C, H.L, and C.P.W contributed to the principal aspects and supervised the progress of the research. All authors reviewed the manuscript.

Corresponding authors

Correspondence to Xin Chen or Ching-Ping Wong.

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The authors declare that they have no competing interests.

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Chen, Y., Shi, D., Mai, X. et al. Design and fabrication of inverted tapered micro-pillars for spontaneously transporting liquid upward. Microfluid Nanofluid 22, 9 (2018). https://doi.org/10.1007/s10404-017-2020-6

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Keywords

  • Inverted tapered micro-pillar
  • Upward liquid transport
  • Fluid dynamics modeling
  • Manufacturing technology